I get it drilled into me all the time about good design, testing code while you write it. Writing the test procedures while you write the code. Devs should test their own code... and PROPER DOCUMENTATION!!! Meeting the requirements, is a bug with the code or with the design... proper use of version control systems, and so on and so on. Lack of REAL quality assurance... preventing bugs from getting into the system in the first place, rather than testing and fixing them after the fact. The good old 20/80 rule, 20% of the work takes 80% of the time... management tends to like things to progress, so they go with the easy stuff, then the hard stuff bites them in the ass near the end of the project, so they have to break things to get other things to work.... just lack of proper design. Design should take most of the time, not testing... but as you said, for a single use project, why bother with all that design when you're going to dump the code base after 2 years...
I'm still largely clueless to the world of programming, but I have done my fair share of testing, all be it closed beta (and alpha) testing for games... long enough to know it is the most degrading part of the IT industry... Devs hate you for poking holes in their code, or for not properly documenting the bug, only to find out that you haven't been given the right version to test and the bug no longer exists. The community naively shouts out that the game hasn't been tested properly because of all these bugs... bugs that testers found and reported weeks (months) ago but the devs haven't been able to fix in time... But software testing and game testing are quite different... I know that much.